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A flexible and free-collector-current of silicon-based anode is facilely prepared just by coating carbon black (CB) and silicon powders layer-by-layer. The resultant electrodes with a “sandwich” structure (CB/Si/CB) are assembled into half-cell and its electrochemical properties are tested. This type of anode exhibits excellent cycling and outstanding rate capability. The superior electrochemical performances are ascribed to both flexible CB-layers to offset the volume expansion of Si-particle. And, the CB-layer with high electric conductivity can provide efficient electron conductive pathways when Si particles react with lithium. More importantly, the CB/Si/CB electrodes without the collerctor (copper-foil) are exhibited high energy density, due to the weight proportion of copper foil is exceeded 60%. The CB/Si/CB electrode is used to assemble full-cell with the same structure as free-collector LCO/CB cathode material. It imposes the energy density of 200 Wh kg −1 , and can keep stable charging-discharging capability at various deformations of shapes. And the flexible-cell of high performance is obtained to meet diverse applications in energy storage devices. Until now, many flexible batteries are put forward by researchers, but these product is faced with the complex production-process, high-cost material, low energy-density. This CB/Si/CB structure is produced with the matching current manufacturing industry and the common raw material, and to get a full-cell of the high energy density. [ABSTRACT FROM AUTHOR]

Development of high-performance SnO 2 anodes is hampered by its peculiar electrochemical behavior, characterized by two processes: conversion and alloying reactions. The conversion reaction being irreversible leads to specific capacities lower than theoretical, however rational design of nanosized SnO 2 can mitigate this issue, though SnO 2 low conductivity and electrode pulverization justify the need of carbon matrices. Some carbon structures proved to be strongly effective at laboratory-scale, but most are too expensive or complicated to obtain for scaling-up. Herein, we exploit the high concentration of oxide and carboxylic surface functional groups of C-NERGY™ Super C45 carbon black for one-pot synthesis of ultrafine SnO 2 nanoparticles over the carbon surface. These functional groups accomplish the hydrolysis/oxidation of SnCl 2 , resulting in finely dispersed SnO 2 nanoparticles (5 nm in average size) growth over C45. Presence of oxygen species on C45 surface, accessible to tin, prevent fast formation of Li 2 O, allowing to achieve high capacity and extreme electrode stability. The assembled cells with SnO 2 /C45 exhibit for more than 400 cycles the reversible capacity of 560 mA h g−1 per pure SnO 2 (after subtracting C45 contribution) at 1C, demonstrating prolonged cycling operation thus providing an interesting opportunity for scalable production of stable and high-capacity battery anodes alternatively to graphite. Image, graphical abstract [ABSTRACT FROM AUTHOR]